Aeromonas hydrophila IN FISH AND HUMANS; PREVALENCE, VIRULOTYPING AND ANTIMICROBIAL RESISTANCE

This work aimed to investigate the virulence factors and antibiotic resistance of A. hydrophila isolated from different sources in Damietta Governorate, Egypt. The samples comprised of tilapia ( Oreochromis niloticus , n=150), mugil ( Mugil cephalus , n=144), human stool (n=102) and fish sellers hand swabs (n=85). A total of 25 A. hydrophila isolates were recovered and molecularly confirmed, of which, 2.7% were from tilapia muscles, 2% from tilapia viscera, 6.3% from mugil viscera and 8.8% from stool samples. No isolates were recovered from mugil muscles and hand swabs. Phenotypic determination of heamolysis, lipolysis, proteolysis and gelatinase activity revealed that 60%, 56%, 60% and 100% were positive, respectively. Molecular identification of haemolysin ( hly ), aerolysin ( aer ), lipase ( lip ) and cytotoxic enterotoxins ( act ) virulence associated genes showed that 28%, 68%, 28% and 16% of the examined isolates were positive, respectively. Antimicrobial susceptibility of the isolates to 17 antibiotics was determined, the most resistance pattern was observed for cefixime (88%), while, all of the isolates were susceptible to imipenem. This study revealed that A. hydrophila isolated from fish and humans showed several virulence factors and exhibit a wide range of antibiotic resistance which is considered a public health hazard as well as. Key words: Aeromonas hydrophila ; virulence; vntibiotic resistance; fish